This invention relates to an apparatus for stirring a highly viscous liquid, and more particularly, to such stirring apparatus having a stirring blade which is capable of both horizontal rotation and vertical movement simultaneously for the uniform stirring of the liquid.
According to the apparatus known in the prior art, a liquid has been stirred exclusively by the rotation of a stirring blade secured to a shaft. The apparatus has very often failed to stir the liquid satisfactorily, especially when the liquid is highly viscous. The liquid in the corners, top and bottom of a tank is not drawn to the stirring blade to be stirred satisfactorily. In view of those difficulties which are often attributable to the viscosity of the liquid to be stirred, it has been proposed to employ a plurality of stirring blades to cause circulation of the liquid through a larger space in the tank, and also to preheat the liquid to be stirred in order to lower its viscosity. But such proposals have turned out to require a larger, more complicated and hence more expensive apparatus.
It is, therefore, an object of this invention to provide an improved liquid stirring apparatus having a stirring blade adapted by a simple mechanism for simultaneous horizontal rotation and vertical movement so that the blade can reach virtually any portion of the volume of a tank holding the liquid to thereby stir the liquid uniformly in a short time.
It is another object of this invention to provide a liquid stirring apparatus wherein the number of rotations of the stirring blade during one stroke of its vertical movement can be selected as desired to best suit the requirements of a particular type of liquid to be stirred.
It is still another object of this invention to provide a liquid stirring apparatus wherein the stroke of vertical movement of the stirring blade can be changed to suit the depth of a liquid tank in addition to alteration of the number of rotations of the blade.
It is a further object of this invention to provide a liquid stirring apparatus which can successfully be operated without causing damaging vibration.